Scanned with small amount of slide mount showing

This is the preferred choice. Notice how this looks more like the original slide as it was projected. It is full-frame with no cropping of the image. We capture the full perimeter of the slide and slightly beyond. This gives a better representation of what the photographer originally saw in their viewfinder. (The image within the red outline below is what will be captured.)

Scanned without slide mount showing

Note that here the image may look cleaner, but it is not as the photographer originally framed it. Part of image is cropped. The top of the rock is missing. And, this is the only option most other transfer houses offer!
(The image within the red outline below is what will be captured.)